My current backup "strategy" is having a NAS with two mirrored HDDs, but this feels more and more dangerous. It only needs one incident and everything is gone. I would love to have an automatic backup over the internet, because I know I'm not going to do it if it's too manual. But I don't know if there are cost-effective solutions for these amounts of data out there. Dropbox and icloud max out at 2TB for example.
The other part of my problem is that I want my photos to be more easily viewable, they are not supposed to rot on a disk. I love scrolling through my iPhone photos, but it's more difficult with RAWs. I have an older Lightroom and a newer CaptureOne catalog. I edit many if not all of my photos, so my workflow has to include these tools. In 99,9% of cases there's just one edit variant of a given photo, so mostly exported jpgs would map 1:1 to the RAWs.
In the end I would like my photos to be easily viewable on the go and searchable (by content ideally). The way I currently do it is to export jpgs into a folder ingested by the Photos application, which merges them into my icloud library. That's nice because it's the native experience on my iPhone and apple's servers are much faster than a connection to my NAS, but it also feels like a solution without a lot of freedom. Also, not all photos are equally important (I usually tag with a good/neutral/bad, not a star system), but I have no way currently to filter on my phone between keepers and other photos. I want to have all available, but would like to be able to hide non-keepers unless I specifically ask for them.
There are many aspects of designing this system going forward, and I would appreciate any input how you deal with this. Please refrain from radical suggestions like "just shoot jpg" or "print the important photos and throw away the rest". I know about all of these lifestyles but I'm generally happy with my own, it just needs polish.
I use my own simple backup script ... for a Hacker News person, it's a toss-up whether it's easier to write your own script or learn a high-level interface like sanoid/syncoid.
As for RAWs, I use a system more or less like yours, but I store my best photos separately from the others, which solves the filtering problem you mention.